Various apparatuses for and methods of transferring cryogenic fluids are already known from the prior art. For example, U.S. Pat. No. 5,429,155 and WO 03/095883 describe couplings suited to transfer cryogenic fluids, particularly liquefied natural gas, methane, air, oxygen or nitrogen, from a stationary storage device into a mobile storage device, for example a vehicle's tank.
In one example, DE 100 55 104 C1 discloses a device for filling a tank with a combustible medium from storage container. The device comprises supply means disposed on the side of the storage container and receiving means disposed on the side of the tank for introducing the medium into the tank. There are provided potential equalization means for equalizing an electrical potential between the storage container and the tank, wherein closing means are unlocked only after the potential equalization means have been connected correctly. DE 10 2004 033567 A1 discloses a connection system for conducting electric power and at least one fluid through a wall for supplying a load by means of a supply module, wherein the supply module is on a first side and the load on a second side of the wall, comprising at least one plug contact arranged in the wall and a socket contact arranged on the supply module and associated with the plug contact. U.S. Pat. No. 5,810,048 A discloses sealing means between two coupling parts. U.S. Pat. No. 6,125,871 A discloses an assembly for transferring chemical fluids. The assembly comprises two connectors connectable with each other. When the connectors are connected with each other, a cleaning liquid may be introduced via a flush inlet of a chamber of one of the connectors and removed via a purge outlet of the chamber. U.S. Pat. No. 5,343,906 A discloses a refueling device for a vehicle, said refueling device further comprising optical transmission means. U.S. Pat. No. 6,202,710 B1 concerns a device for refueling a vehicle.
Here, it is to be noted that, above all, the vehicle has to be earthed separately in order to establish charge equalization among both storage devices or the vehicle. Usually, this is done by manually attaching and earthing cable to a metal component of the vehicle before connecting the tank coupling to the tank.
There is a risk of impurities on the contact surfaces of the couplings preventing a perfect seal, particularly in the case of cryogenic fluids. Such impurities have to be removed manually prior to the fill-up. Usually, dehumidified compressed air or nitrogen is used for this. An imperfect seal not only carries the risk of the gas being emitted but also, above all, of humidity or oxygen seeping in and thus causing icing of the valve or the formation of explosive mixtures. Icing of the valve may also damage the seal in the event of the coupling being separated too quickly.
Since both earthing and cleansing are to be performed manually prior to attaching the tank coupling, there is the risk of these steps being forgotten or executed improperly.